Josephson junctions description

To proceed, we begin with the fully quantum mechanical description of the system in terms of a Keldysh action for a single variable [10, 9], that incorporates information about FCS of the normal conductor and the properties of the Josephson junction. We calculate the escape rate by considering saddle-point trajectories of the action, A, that connect the potential minimum with the nearest potential maximum. With exponential accuracy, the rate is given by T exp(— ImA/ft). 

The PT model is frequently used as a minimalistic approximation for more complex models. For instance, it is the mean-field version of the Frenkel Kontorova (FK) model as stressed by D. S. Fisher [29,83] in the context of the motion of charge-density waves. The (mean-field) description of driven, coupled Josephson junctions is also mathematically equivalent to the PT model. This equivalence has been exploited by Baumberger and Carol for a model that, however, was termed the lumped junction model [84] and that attempts to... 

A Josephson junction consists of two closely spaced superconductors separated by a weak connection (Figure 4.6.1). This connection may be provided by an insulator, a normal metal, a semiconductor, a weakened superconductor, or some other material that weakly couples the two superconductors. The two superconducting regions may be characterized by quantum mechanical wave functions and 2 respectively. Normally a much more complicated description would be necessary because... 

We will describe two different types of Josephson junctions (i) The Anderson-Dayem bridges, the behavior of which can be interpreted very nicely in terms of dissipative structures, but for which the theoretical description is not so simple. 

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